Is troubleshooting and replace a defrost sensor and/or a defrost circuit board a DIY project?

[gfr92y]

Forum Members,

I have a 12-year-old Bryant / Carrier / Model 25HBC336W0030010 heat pump that was given a clean bill of health last October by HVAC repair company A.

Monday night, it frosted/froze up and Tuesday morning, a tech from HVAC repair company B said the refrigerant level was fine but with doing a resistivity test or an ice cube and screwdriver, decided the defrost sensor and defrost circuit board needed to be replaced.

I know essentially nothing about heat pumps, but have sufficient technical acumen to not have any mechanics touch any of my cars or my children’s cars in 23 years (except for aligning and balancing tires).

With your help, can I confirm whether or not the defrost sensor and the defrost circuit board are bad and replace the bad component or both components if that it the practice with Heat pumps?

Thank you very much for your assistance on this project.

Sincerely,

Gfr92y

 

[AC Power]

Yes, the technician (of company B) is likely right. He attempted to prompt the unit into a defrost cycle by "fooling" the sensor in thinking the coil was frozen with a piece of ice. The resistivity test is to determine the state of the contacts in the sensor, that is if their standard form A NO dry contacts (or form B for fail-safe) or there 0-10ma. He did it right.

Only problem is, that doesn't indicate if the sensor OR the board is dead....it only tells you at least one of them is dead.

If it where me, I would direct him to change both.

 

[gfr92y]

Thanks for confirming that!

 

[gfr92y]

Yes, the technician (of company B) is likely right. He attempted to prompt the unit into a defrost cycle by "fooling" the sensor in thinking the coil was frozen with a piece of ice. The resistivity test is to determine the state of the contacts in the sensor, that is if their standard form A NO dry contacts (or form B for fail-safe) or there 0-10ma. He did it right.

Only problem is, that doesn't indicate if the sensor OR the board is dead....it only tells you at least one of them is dead.

If it where me, I would direct him to change both.

Thanks for confirming that!

 

[AC Power]

Your Welcome. I hope it works for you!